Mystery deepens over Antarctic mountain range buried under miles of iceNovember 9th, 2008 - 12:05 pm ICT by ANI
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Washington, Nov 9 (ANI): A new study has said that the existence of a massive Antarctic mountain range buried under miles of ice has become an even deeper mystery.
According to a report in National Geographic News, the little-researched Gamburtsev Mountains, the range in question, seems to challenge geologic patterns seen in other mountain ranges on Earth.
For one, the range is situated in the middle of the continent instead of on the edge, like most other mountains.
The range’’s high peaks reach an elevation of about 10,000 feet (more than 3,000 meters)heights typical of relatively young mountain ranges, such as the spiky Rockies and the European Alps.
New findings based on river sediments, which suggest the range is more than 500 million years old, are intriguing, according to experts.
Older mountains, such as the Appalachian range in the eastern U.S., are thought to be shorter and less rugged after hundreds of millions of years of erosion.
Because the Gamburtsev range is tall, some scientists have argued it must have formed relatively recentlywithin the last 60 million years or so.
Because it’’s not near a tectonic boundary, some have suggested the range rose up as the result of magma buildup around a theoretical volcanic hot spot.
“The hypothesis that the mountains are derived from young volcanic activity is hard to reconcile with our data,” said study lead author Tina van de Flierdt of the Imperial College London.
Scientists examined sediments collected from a coastal area that would have been a vast delta about 35 million years ago, when Antarctica’’s rivers carried flowing water instead of glacier ice.
If the mountains were made of relatively recent volcanic material, some of it should have been in the sediment as Gamburtsev runoff passed through the delta.
Instead, all mineral grains the researchers dated, such as zircon and hornblende, were more than 500 million years old.
“Volcanic activity of the extent to form a mountain range bigger than the European Alps would leave a ”geochemical fingerprint” in the preglacial to present-day sediments. We simply can”t see this fingerprint,” van de Flierdt said.
The study makes a good case for the theory that the mountains were not formed by recent volcanic activity, according to University of Arizona geochemist Peter Reiners.
“If the mountains themselves are anywhere close to the same age as the rocks, then the Gamburtsevs are trying to tell us something about how really old topography can persist for hundreds of millions of years without being worn down by water, wind, and glaciers,” he said. (ANI)
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